I must show, using integration by parts that for all positive . I've tried but I don't get the result. The fact that the integral is dt and that the function depends of x is responsible of my fail.
Can you start me up?

Jun 23rd 2008, 02:03 PM

Mathstud28

Quote:

Originally Posted by arbolis

I must show, using integration by parts that for all positive . I've tried but I don't get the result. The fact that the integral is dt and that the function depends of x is responsible of my fail.
Can you start me up?

I think the better way not to be confused is to take n instead of x. So that we're almost sure not to take n as a variable.

Oops!! I got confused! I thought I had to do it with respect to x... how could I understand then, that if , then !!!
My exam of Calculus II is coming up next 21st of July, so I have all the time to fix such problems of mine. A big thanks to you.

Jun 23rd 2008, 02:46 PM

Mathstud28

Quote:

Originally Posted by arbolis

, Oops!! I got confused! I thought I had to do it with respect to x... how could I understand then, that if , then !!!
My exam of Calculus II is coming up next 21st of July, so I have all the time to fix such problems of mine. A big thanks to you.

Although t is a dummy variable (a place holder) in this context as moo said since x is a fixed value and t is the variable you must differentiate in respect to t